function campanas(num)
    Fs = 44.1e3;
    switch (num)
        case 1	% Campana 1
            fc = 110;
            fm = 220;
            tau = 2;
            A0 = 1;
            I0 = 10;
            duration = 6;
        case 2	% Campana 2
            fc = 220;
            fm = 440;
            tau = 2;
            A0 = 2;
            I0 = 5;
            duration = 6;
        case 3	% Campana 3
            fc = 110;
            fm = 220;
            tau = 12;
            A0 = 3;
            I0 = 10;
            duration = 3;
        case 4  % Campana 4
            fc = 110;
            fm = 220;
            tau = 0.3;
            A0 = 2;
            I0 = 10;
            duration = 5;
        case 5	% Campana 5
            fc = 250;
            fm = 350;
            tau = 2;
            A0 = 2;
            I0 = 5;
            duration = 5;
        case 6	% Campana 6
            fc = 250;
            fm = 350;
            tau = 2;
            A0 = 3;
            I0 = 3;
            duration = 5;
    end

    data.fc = fc;
    data.fm = fm;
    t = 0:1/Fs:duration-1/Fs;
    data.A = A0 * exp(-t/tau);
    data.I = I0 * exp(-t/tau);

    out = modulated_frequency(duration,data,Fs);
    sound(out,Fs);
    audiowrite('campana5.wav',out,Fs);
end